drivers/power/supply/power_supply_core.c

   1 /*
   2  *  Universal power supply monitor class
   3  *
   4  *  Copyright © 2007  Anton Vorontsov <cbou@mail.ru>
   5  *  Copyright © 2004  Szabolcs Gyurko
   6  *  Copyright © 2003  Ian Molton <spyro@f2s.com>
   7  *
   8  *  Modified: 2004, Oct     Szabolcs Gyurko
   9  *
  10  *  You may use this code as per GPL version 2
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17 #include <linux/delay.h>
  18 #include <linux/device.h>
  19 #include <linux/notifier.h>
  20 #include <linux/err.h>
  21 #include <linux/of.h>
  22 #include <linux/power_supply.h>
  23 #include <linux/thermal.h>
  24 #include "power_supply.h"
  25
  26 /* exported for the APM Power driver, APM emulation */
  27 struct class *power_supply_class;
  28 EXPORT_SYMBOL_GPL(power_supply_class);
  29
  30 ATOMIC_NOTIFIER_HEAD(power_supply_notifier);
  31 EXPORT_SYMBOL_GPL(power_supply_notifier);
  32
  33 static struct device_type power_supply_dev_type;
  34
  35 #define POWER_SUPPLY_DEFERRED_REGISTER_TIME     msecs_to_jiffies(10)
  36
  37 static bool __power_supply_is_supplied_by(struct power_supply *supplier,
  38                                          struct power_supply *supply)
  39 {
  40         int i;
  41
  42         if (!supply->supplied_from && !supplier->supplied_to)
  43                 return false;
  44
  45         /* Support both supplied_to and supplied_from modes */
  46         if (supply->supplied_from) {
  47                 if (!supplier->desc->name)
  48                         return false;
  49                 for (i = 0; i < supply->num_supplies; i++)
  50                         if (!strcmp(supplier->desc->name, supply->supplied_from[i]))
  51                                 return true;
  52         } else {
  53                 if (!supply->desc->name)
  54                         return false;
  55                 for (i = 0; i < supplier->num_supplicants; i++)
  56                         if (!strcmp(supplier->supplied_to[i], supply->desc->name))
  57                                 return true;
  58         }
  59
  60         return false;
  61 }
  62
  63 static int __power_supply_changed_work(struct device *dev, void *data)
  64 {
  65         struct power_supply *psy = data;
  66         struct power_supply *pst = dev_get_drvdata(dev);
  67
  68         if (__power_supply_is_supplied_by(psy, pst)) {
  69                 if (pst->desc->external_power_changed)
  70                         pst->desc->external_power_changed(pst);
  71         }
  72
  73         return 0;
  74 }
  75
  76 static void power_supply_changed_work(struct work_struct *work)
  77 {
  78         unsigned long flags;
  79         struct power_supply *psy = container_of(work, struct power_supply,
  80                                                 changed_work);
  81
  82         dev_dbg(&psy->dev, "%s\n", __func__);
  83
  84         spin_lock_irqsave(&psy->changed_lock, flags);
  85         /*
  86          * Check 'changed' here to avoid issues due to race between
  87          * power_supply_changed() and this routine. In worst case
  88          * power_supply_changed() can be called again just before we take above
  89          * lock. During the first call of this routine we will mark 'changed' as
  90          * false and it will stay false for the next call as well.
  91          */
  92         if (likely(psy->changed)) {
  93                 psy->changed = false;
  94                 spin_unlock_irqrestore(&psy->changed_lock, flags);
  95                 class_for_each_device(power_supply_class, NULL, psy,
  96                                       __power_supply_changed_work);
  97                 power_supply_update_leds(psy);
  98                 atomic_notifier_call_chain(&power_supply_notifier,
  99                                 PSY_EVENT_PROP_CHANGED, psy);
 100                 kobject_uevent(&psy->dev.kobj, KOBJ_CHANGE);
 101                 spin_lock_irqsave(&psy->changed_lock, flags);
 102         }
 103
 104         /*
 105          * Hold the wakeup_source until all events are processed.
 106          * power_supply_changed() might have called again and have set 'changed'
 107          * to true.
 108          */
 109         if (likely(!psy->changed))
 110                 pm_relax(&psy->dev);
 111         spin_unlock_irqrestore(&psy->changed_lock, flags);
 112 }
 113
 114 void power_supply_changed(struct power_supply *psy)
 115 {
 116         unsigned long flags;
 117
 118         dev_dbg(&psy->dev, "%s\n", __func__);
 119
 120         spin_lock_irqsave(&psy->changed_lock, flags);
 121         psy->changed = true;
 122         pm_stay_awake(&psy->dev);
 123         spin_unlock_irqrestore(&psy->changed_lock, flags);
 124         schedule_work(&psy->changed_work);
 125 }
 126 EXPORT_SYMBOL_GPL(power_supply_changed);
 127
 128 /*
 129  * Notify that power supply was registered after parent finished the probing.
 130  *
 131  * Often power supply is registered from driver's probe function. However
 132  * calling power_supply_changed() directly from power_supply_register()
 133  * would lead to execution of get_property() function provided by the driver
 134  * too early - before the probe ends.
 135  *
 136  * Avoid that by waiting on parent's mutex.
 137  */
 138 static void power_supply_deferred_register_work(struct work_struct *work)
 139 {
 140         struct power_supply *psy = container_of(work, struct power_supply,
 141                                                 deferred_register_work.work);
 142
 143         if (psy->dev.parent) {
 144                 while (!mutex_trylock(&psy->dev.parent->mutex)) {
 145                         if (psy->removing)
 146                                 return;
 147                         msleep(10);
 148                 }
 149         }
 150
 151         power_supply_changed(psy);
 152
 153         if (psy->dev.parent)
 154                 mutex_unlock(&psy->dev.parent->mutex);
 155 }
 156
 157 #ifdef CONFIG_OF
 158 #include <linux/of.h>
 159
 160 static int __power_supply_populate_supplied_from(struct device *dev,
 161                                                  void *data)
 162 {
 163         struct power_supply *psy = data;
 164         struct power_supply *epsy = dev_get_drvdata(dev);
 165         struct device_node *np;
 166         int i = 0;
 167
 168         do {
 169                 np = of_parse_phandle(psy->of_node, "power-supplies", i++);
 170                 if (!np)
 171                         break;
 172
 173                 if (np == epsy->of_node) {
 174                         dev_info(&psy->dev, "%s: Found supply : %s\n",
 175                                 psy->desc->name, epsy->desc->name);
 176                         psy->supplied_from[i-1] = (char *)epsy->desc->name;
 177                         psy->num_supplies++;
 178                         of_node_put(np);
 179                         break;
 180                 }
 181                 of_node_put(np);
 182         } while (np);
 183
 184         return 0;
 185 }
 186
 187 static int power_supply_populate_supplied_from(struct power_supply *psy)
 188 {
 189         int error;
 190
 191         error = class_for_each_device(power_supply_class, NULL, psy,
 192                                       __power_supply_populate_supplied_from);
 193
 194         dev_dbg(&psy->dev, "%s %d\n", __func__, error);
 195
 196         return error;
 197 }
 198
 199 static int  __power_supply_find_supply_from_node(struct device *dev,
 200                                                  void *data)
 201 {
 202         struct device_node *np = data;
 203         struct power_supply *epsy = dev_get_drvdata(dev);
 204
 205         /* returning non-zero breaks out of class_for_each_device loop */
 206         if (epsy->of_node == np)
 207                 return 1;
 208
 209         return 0;
 210 }
 211
 212 static int power_supply_find_supply_from_node(struct device_node *supply_node)
 213 {
 214         int error;
 215
 216         /*
 217          * class_for_each_device() either returns its own errors or values
 218          * returned by __power_supply_find_supply_from_node().
 219          *
 220          * __power_supply_find_supply_from_node() will return 0 (no match)
 221          * or 1 (match).
 222          *
 223          * We return 0 if class_for_each_device() returned 1, -EPROBE_DEFER if
 224          * it returned 0, or error as returned by it.
 225          */
 226         error = class_for_each_device(power_supply_class, NULL, supply_node,
 227                                        __power_supply_find_supply_from_node);
 228
 229         return error ? (error == 1 ? 0 : error) : -EPROBE_DEFER;
 230 }
 231
 232 static int power_supply_check_supplies(struct power_supply *psy)
 233 {
 234         struct device_node *np;
 235         int cnt = 0;
 236
 237         /* If there is already a list honor it */
 238         if (psy->supplied_from && psy->num_supplies > 0)
 239                 return 0;
 240
 241         /* No device node found, nothing to do */
 242         if (!psy->of_node)
 243                 return 0;
 244
 245         do {
 246                 int ret;
 247
 248                 np = of_parse_phandle(psy->of_node, "power-supplies", cnt++);
 249                 if (!np)
 250                         break;
 251
 252                 ret = power_supply_find_supply_from_node(np);
 253                 of_node_put(np);
 254
 255                 if (ret) {
 256                         dev_dbg(&psy->dev, "Failed to find supply!\n");
 257                         return ret;
 258                 }
 259         } while (np);
 260
 261         /* Missing valid "power-supplies" entries */
 262         if (cnt == 1)
 263                 return 0;
 264
 265         /* All supplies found, allocate char ** array for filling */
 266         psy->supplied_from = devm_kzalloc(&psy->dev, sizeof(psy->supplied_from),
 267                                           GFP_KERNEL);
 268         if (!psy->supplied_from)
 269                 return -ENOMEM;
 270
 271         *psy->supplied_from = devm_kzalloc(&psy->dev,
 272                                            sizeof(char *) * (cnt - 1),
 273                                            GFP_KERNEL);
 274         if (!*psy->supplied_from)
 275                 return -ENOMEM;
 276
 277         return power_supply_populate_supplied_from(psy);
 278 }
 279 #else
 280 static int power_supply_check_supplies(struct power_supply *psy)
 281 {
 282         int nval, ret;
 283
 284         if (!psy->dev.parent)
 285                 return 0;
 286
 287         nval = device_property_read_string_array(psy->dev.parent,
 288                                                  "supplied-from", NULL, 0);
 289         if (nval <= 0)
 290                 return 0;
 291
 292         psy->supplied_from = devm_kmalloc_array(&psy->dev, nval,
 293                                                 sizeof(char *), GFP_KERNEL);
 294         if (!psy->supplied_from)
 295                 return -ENOMEM;
 296
 297         ret = device_property_read_string_array(psy->dev.parent,
 298                 "supplied-from", (const char **)psy->supplied_from, nval);
 299         if (ret < 0)
 300                 return ret;
 301
 302         psy->num_supplies = nval;
 303
 304         return 0;
 305 }
 306 #endif
 307
 308 struct psy_am_i_supplied_data {
 309         struct power_supply *psy;
 310         unsigned int count;
 311 };
 312
 313 static int __power_supply_am_i_supplied(struct device *dev, void *_data)
 314 {
 315         union power_supply_propval ret = {0,};
 316         struct power_supply *epsy = dev_get_drvdata(dev);
 317         struct psy_am_i_supplied_data *data = _data;
 318
 319         if (__power_supply_is_supplied_by(epsy, data->psy)) {
 320                 data->count++;
 321                 if (!epsy->desc->get_property(epsy, POWER_SUPPLY_PROP_ONLINE,
 322                                         &ret))
 323                         return ret.intval;
 324         }
 325
 326         return 0;
 327 }
 328
 329 int power_supply_am_i_supplied(struct power_supply *psy)
 330 {
 331         struct psy_am_i_supplied_data data = { psy, 0 };
 332         int error;
 333
 334         error = class_for_each_device(power_supply_class, NULL, &data,
 335                                       __power_supply_am_i_supplied);
 336
 337         dev_dbg(&psy->dev, "%s count %u err %d\n", __func__, data.count, error);
 338
 339         if (data.count == 0)
 340                 return -ENODEV;
 341
 342         return error;
 343 }
 344 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
 345
 346 static int __power_supply_is_system_supplied(struct device *dev, void *data)
 347 {
 348         union power_supply_propval ret = {0,};
 349         struct power_supply *psy = dev_get_drvdata(dev);
 350         unsigned int *count = data;
 351
 352         if (!psy->desc->get_property(psy, POWER_SUPPLY_PROP_SCOPE, &ret))
 353                 if (ret.intval == POWER_SUPPLY_SCOPE_DEVICE)
 354                         return 0;
 355
 356         (*count)++;
 357         if (psy->desc->type != POWER_SUPPLY_TYPE_BATTERY)
 358                 if (!psy->desc->get_property(psy, POWER_SUPPLY_PROP_ONLINE,
 359                                         &ret))
 360                         return ret.intval;
 361
 362         return 0;
 363 }
 364
 365 int power_supply_is_system_supplied(void)
 366 {
 367         int error;
 368         unsigned int count = 0;
 369
 370         error = class_for_each_device(power_supply_class, NULL, &count,
 371                                       __power_supply_is_system_supplied);
 372
 373         /*
 374          * If no system scope power class device was found at all, most probably we
 375          * are running on a desktop system, so assume we are on mains power.
 376          */
 377         if (count == 0)
 378                 return 1;
 379
 380         return error;
 381 }
 382 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
 383
 384 static int __power_supply_get_supplier_max_current(struct device *dev,
 385                                                    void *data)
 386 {
 387         union power_supply_propval ret = {0,};
 388         struct power_supply *epsy = dev_get_drvdata(dev);
 389         struct power_supply *psy = data;
 390
 391         if (__power_supply_is_supplied_by(epsy, psy))
 392                 if (!epsy->desc->get_property(epsy,
 393                                               POWER_SUPPLY_PROP_CURRENT_MAX,
 394                                               &ret))
 395                         return ret.intval;
 396
 397         return 0;
 398 }
 399
 400 int power_supply_set_input_current_limit_from_supplier(struct power_supply *psy)
 401 {
 402         union power_supply_propval val = {0,};
 403         int curr;
 404
 405         if (!psy->desc->set_property)
 406                 return -EINVAL;
 407
 408         /*
 409          * This function is not intended for use with a supply with multiple
 410          * suppliers, we simply pick the first supply to report a non 0
 411          * max-current.
 412          */
 413         curr = class_for_each_device(power_supply_class, NULL, psy,
 414                                       __power_supply_get_supplier_max_current);
 415         if (curr <= 0)
 416                 return (curr == 0) ? -ENODEV : curr;
 417
 418         val.intval = curr;
 419
 420         return psy->desc->set_property(psy,
 421                                 POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT, &val);
 422 }
 423 EXPORT_SYMBOL_GPL(power_supply_set_input_current_limit_from_supplier);
 424
 425 int power_supply_set_battery_charged(struct power_supply *psy)
 426 {
 427         if (atomic_read(&psy->use_cnt) >= 0 &&
 428                         psy->desc->type == POWER_SUPPLY_TYPE_BATTERY &&
 429                         psy->desc->set_charged) {
 430                 psy->desc->set_charged(psy);
 431                 return 0;
 432         }
 433
 434         return -EINVAL;
 435 }
 436 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
 437
 438 static int power_supply_match_device_by_name(struct device *dev, const void *data)
 439 {
 440         const char *name = data;
 441         struct power_supply *psy = dev_get_drvdata(dev);
 442
 443         return strcmp(psy->desc->name, name) == 0;
 444 }
 445
 446 /**
 447  * power_supply_get_by_name() - Search for a power supply and returns its ref
 448  * @name: Power supply name to fetch
 449  *
 450  * If power supply was found, it increases reference count for the
 451  * internal power supply's device. The user should power_supply_put()
 452  * after usage.
 453  *
 454  * Return: On success returns a reference to a power supply with
 455  * matching name equals to @name, a NULL otherwise.
 456  */
 457 struct power_supply *power_supply_get_by_name(const char *name)
 458 {
 459         struct power_supply *psy = NULL;
 460         struct device *dev = class_find_device(power_supply_class, NULL, name,
 461                                         power_supply_match_device_by_name);
 462
 463         if (dev) {
 464                 psy = dev_get_drvdata(dev);
 465                 atomic_inc(&psy->use_cnt);
 466         }
 467
 468         return psy;
 469 }
 470 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
 471
 472 /**
 473  * power_supply_put() - Drop reference obtained with power_supply_get_by_name
 474  * @psy: Reference to put
 475  *
 476  * The reference to power supply should be put before unregistering
 477  * the power supply.
 478  */
 479 void power_supply_put(struct power_supply *psy)
 480 {
 481         might_sleep();
 482
 483         atomic_dec(&psy->use_cnt);
 484         put_device(&psy->dev);
 485 }
 486 EXPORT_SYMBOL_GPL(power_supply_put);
 487
 488 #ifdef CONFIG_OF
 489 static int power_supply_match_device_node(struct device *dev, const void *data)
 490 {
 491         return dev->parent && dev->parent->of_node == data;
 492 }
 493
 494 /**
 495  * power_supply_get_by_phandle() - Search for a power supply and returns its ref
 496  * @np: Pointer to device node holding phandle property
 497  * @property: Name of property holding a power supply name
 498  *
 499  * If power supply was found, it increases reference count for the
 500  * internal power supply's device. The user should power_supply_put()
 501  * after usage.
 502  *
 503  * Return: On success returns a reference to a power supply with
 504  * matching name equals to value under @property, NULL or ERR_PTR otherwise.
 505  */
 506 struct power_supply *power_supply_get_by_phandle(struct device_node *np,
 507                                                         const char *property)
 508 {
 509         struct device_node *power_supply_np;
 510         struct power_supply *psy = NULL;
 511         struct device *dev;
 512
 513         power_supply_np = of_parse_phandle(np, property, 0);
 514         if (!power_supply_np)
 515                 return ERR_PTR(-ENODEV);
 516
 517         dev = class_find_device(power_supply_class, NULL, power_supply_np,
 518                                                 power_supply_match_device_node);
 519
 520         of_node_put(power_supply_np);
 521
 522         if (dev) {
 523                 psy = dev_get_drvdata(dev);
 524                 atomic_inc(&psy->use_cnt);
 525         }
 526
 527         return psy;
 528 }
 529 EXPORT_SYMBOL_GPL(power_supply_get_by_phandle);
 530
 531 static void devm_power_supply_put(struct device *dev, void *res)
 532 {
 533         struct power_supply **psy = res;
 534
 535         power_supply_put(*psy);
 536 }
 537
 538 /**
 539  * devm_power_supply_get_by_phandle() - Resource managed version of
 540  *  power_supply_get_by_phandle()
 541  * @dev: Pointer to device holding phandle property
 542  * @property: Name of property holding a power supply phandle
 543  *
 544  * Return: On success returns a reference to a power supply with
 545  * matching name equals to value under @property, NULL or ERR_PTR otherwise.
 546  */
 547 struct power_supply *devm_power_supply_get_by_phandle(struct device *dev,
 548                                                       const char *property)
 549 {
 550         struct power_supply **ptr, *psy;
 551
 552         if (!dev->of_node)
 553                 return ERR_PTR(-ENODEV);
 554
 555         ptr = devres_alloc(devm_power_supply_put, sizeof(*ptr), GFP_KERNEL);
 556         if (!ptr)
 557                 return ERR_PTR(-ENOMEM);
 558
 559         psy = power_supply_get_by_phandle(dev->of_node, property);
 560         if (IS_ERR_OR_NULL(psy)) {
 561                 devres_free(ptr);
 562         } else {
 563                 *ptr = psy;
 564                 devres_add(dev, ptr);
 565         }
 566         return psy;
 567 }
 568 EXPORT_SYMBOL_GPL(devm_power_supply_get_by_phandle);
 569 #endif /* CONFIG_OF */
 570
 571 int power_supply_get_battery_info(struct power_supply *psy,
 572                                   struct power_supply_battery_info *info)
 573 {
 574         struct device_node *battery_np;
 575         const char *value;
 576         int err;
 577
 578         info->energy_full_design_uwh         = -EINVAL;
 579         info->charge_full_design_uah         = -EINVAL;
 580         info->voltage_min_design_uv          = -EINVAL;
 581         info->precharge_current_ua           = -EINVAL;
 582         info->charge_term_current_ua         = -EINVAL;
 583         info->constant_charge_current_max_ua = -EINVAL;
 584         info->constant_charge_voltage_max_uv = -EINVAL;
 585
 586         if (!psy->of_node) {
 587                 dev_warn(&psy->dev, "%s currently only supports devicetree\n",
 588                          __func__);
 589                 return -ENXIO;
 590         }
 591
 592         battery_np = of_parse_phandle(psy->of_node, "monitored-battery", 0);
 593         if (!battery_np)
 594                 return -ENODEV;
 595
 596         err = of_property_read_string(battery_np, "compatible", &value);
 597         if (err)
 598                 return err;
 599
 600         if (strcmp("simple-battery", value))
 601                 return -ENODEV;
 602
 603         /* The property and field names below must correspond to elements
 604          * in enum power_supply_property. For reasoning, see
 605          * Documentation/power/power_supply_class.txt.
 606          */
 607
 608         of_property_read_u32(battery_np, "energy-full-design-microwatt-hours",
 609                              &info->energy_full_design_uwh);
 610         of_property_read_u32(battery_np, "charge-full-design-microamp-hours",
 611                              &info->charge_full_design_uah);
 612         of_property_read_u32(battery_np, "voltage-min-design-microvolt",
 613                              &info->voltage_min_design_uv);
 614         of_property_read_u32(battery_np, "precharge-current-microamp",
 615                              &info->precharge_current_ua);
 616         of_property_read_u32(battery_np, "charge-term-current-microamp",
 617                              &info->charge_term_current_ua);
 618         of_property_read_u32(battery_np, "constant_charge_current_max_microamp",
 619                              &info->constant_charge_current_max_ua);
 620         of_property_read_u32(battery_np, "constant_charge_voltage_max_microvolt",
 621                              &info->constant_charge_voltage_max_uv);
 622
 623         return 0;
 624 }
 625 EXPORT_SYMBOL_GPL(power_supply_get_battery_info);
 626
 627 int power_supply_get_property(struct power_supply *psy,
 628                             enum power_supply_property psp,
 629                             union power_supply_propval *val)
 630 {
 631         if (atomic_read(&psy->use_cnt) <= 0) {
 632                 if (!psy->initialized)
 633                         return -EAGAIN;
 634                 return -ENODEV;
 635         }
 636
 637         return psy->desc->get_property(psy, psp, val);
 638 }
 639 EXPORT_SYMBOL_GPL(power_supply_get_property);
 640
 641 int power_supply_set_property(struct power_supply *psy,
 642                             enum power_supply_property psp,
 643                             const union power_supply_propval *val)
 644 {
 645         if (atomic_read(&psy->use_cnt) <= 0 || !psy->desc->set_property)
 646                 return -ENODEV;
 647
 648         return psy->desc->set_property(psy, psp, val);
 649 }
 650 EXPORT_SYMBOL_GPL(power_supply_set_property);
 651
 652 int power_supply_property_is_writeable(struct power_supply *psy,
 653                                         enum power_supply_property psp)
 654 {
 655         if (atomic_read(&psy->use_cnt) <= 0 ||
 656                         !psy->desc->property_is_writeable)
 657                 return -ENODEV;
 658
 659         return psy->desc->property_is_writeable(psy, psp);
 660 }
 661 EXPORT_SYMBOL_GPL(power_supply_property_is_writeable);
 662
 663 void power_supply_external_power_changed(struct power_supply *psy)
 664 {
 665         if (atomic_read(&psy->use_cnt) <= 0 ||
 666                         !psy->desc->external_power_changed)
 667                 return;
 668
 669         psy->desc->external_power_changed(psy);
 670 }
 671 EXPORT_SYMBOL_GPL(power_supply_external_power_changed);
 672
 673 int power_supply_powers(struct power_supply *psy, struct device *dev)
 674 {
 675         return sysfs_create_link(&psy->dev.kobj, &dev->kobj, "powers");
 676 }
 677 EXPORT_SYMBOL_GPL(power_supply_powers);
 678
 679 static void power_supply_dev_release(struct device *dev)
 680 {
 681         struct power_supply *psy = container_of(dev, struct power_supply, dev);
 682         pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
 683         kfree(psy);
 684 }
 685
 686 int power_supply_reg_notifier(struct notifier_block *nb)
 687 {
 688         return atomic_notifier_chain_register(&power_supply_notifier, nb);
 689 }
 690 EXPORT_SYMBOL_GPL(power_supply_reg_notifier);
 691
 692 void power_supply_unreg_notifier(struct notifier_block *nb)
 693 {
 694         atomic_notifier_chain_unregister(&power_supply_notifier, nb);
 695 }
 696 EXPORT_SYMBOL_GPL(power_supply_unreg_notifier);
 697
 698 #ifdef CONFIG_THERMAL
 699 static int power_supply_read_temp(struct thermal_zone_device *tzd,
 700                 int *temp)
 701 {
 702         struct power_supply *psy;
 703         union power_supply_propval val;
 704         int ret;
 705
 706         WARN_ON(tzd == NULL);
 707         psy = tzd->devdata;
 708         ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);
 709         if (ret)
 710                 return ret;
 711
 712         /* Convert tenths of degree Celsius to milli degree Celsius. */
 713         *temp = val.intval * 100;
 714
 715         return ret;
 716 }
 717
 718 static struct thermal_zone_device_ops psy_tzd_ops = {
 719         .get_temp = power_supply_read_temp,
 720 };
 721
 722 static int psy_register_thermal(struct power_supply *psy)
 723 {
 724         int i;
 725
 726         if (psy->desc->no_thermal)
 727                 return 0;
 728
 729         /* Register battery zone device psy reports temperature */
 730         for (i = 0; i < psy->desc->num_properties; i++) {
 731                 if (psy->desc->properties[i] == POWER_SUPPLY_PROP_TEMP) {
 732                         psy->tzd = thermal_zone_device_register(psy->desc->name,
 733                                         0, 0, psy, &psy_tzd_ops, NULL, 0, 0);
 734                         return PTR_ERR_OR_ZERO(psy->tzd);
 735                 }
 736         }
 737         return 0;
 738 }
 739
 740 static void psy_unregister_thermal(struct power_supply *psy)
 741 {
 742         if (IS_ERR_OR_NULL(psy->tzd))
 743                 return;
 744         thermal_zone_device_unregister(psy->tzd);
 745 }
 746
 747 /* thermal cooling device callbacks */
 748 static int ps_get_max_charge_cntl_limit(struct thermal_cooling_device *tcd,
 749                                         unsigned long *state)
 750 {
 751         struct power_supply *psy;
 752         union power_supply_propval val;
 753         int ret;
 754
 755         psy = tcd->devdata;
 756         ret = power_supply_get_property(psy,
 757                         POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val);
 758         if (ret)
 759                 return ret;
 760
 761         *state = val.intval;
 762
 763         return ret;
 764 }
 765
 766 static int ps_get_cur_chrage_cntl_limit(struct thermal_cooling_device *tcd,
 767                                         unsigned long *state)
 768 {
 769         struct power_supply *psy;
 770         union power_supply_propval val;
 771         int ret;
 772
 773         psy = tcd->devdata;
 774         ret = power_supply_get_property(psy,
 775                         POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
 776         if (ret)
 777                 return ret;
 778
 779         *state = val.intval;
 780
 781         return ret;
 782 }
 783
 784 static int ps_set_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
 785                                         unsigned long state)
 786 {
 787         struct power_supply *psy;
 788         union power_supply_propval val;
 789         int ret;
 790
 791         psy = tcd->devdata;
 792         val.intval = state;
 793         ret = psy->desc->set_property(psy,
 794                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
 795
 796         return ret;
 797 }
 798
 799 static const struct thermal_cooling_device_ops psy_tcd_ops = {
 800         .get_max_state = ps_get_max_charge_cntl_limit,
 801         .get_cur_state = ps_get_cur_chrage_cntl_limit,
 802         .set_cur_state = ps_set_cur_charge_cntl_limit,
 803 };
 804
 805 static int psy_register_cooler(struct power_supply *psy)
 806 {
 807         int i;
 808
 809         /* Register for cooling device if psy can control charging */
 810         for (i = 0; i < psy->desc->num_properties; i++) {
 811                 if (psy->desc->properties[i] ==
 812                                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT) {
 813                         psy->tcd = thermal_cooling_device_register(
 814                                                         (char *)psy->desc->name,
 815                                                         psy, &psy_tcd_ops);
 816                         return PTR_ERR_OR_ZERO(psy->tcd);
 817                 }
 818         }
 819         return 0;
 820 }
 821
 822 static void psy_unregister_cooler(struct power_supply *psy)
 823 {
 824         if (IS_ERR_OR_NULL(psy->tcd))
 825                 return;
 826         thermal_cooling_device_unregister(psy->tcd);
 827 }
 828 #else
 829 static int psy_register_thermal(struct power_supply *psy)
 830 {
 831         return 0;
 832 }
 833
 834 static void psy_unregister_thermal(struct power_supply *psy)
 835 {
 836 }
 837
 838 static int psy_register_cooler(struct power_supply *psy)
 839 {
 840         return 0;
 841 }
 842
 843 static void psy_unregister_cooler(struct power_supply *psy)
 844 {
 845 }
 846 #endif
 847
 848 static struct power_supply *__must_check
 849 __power_supply_register(struct device *parent,
 850                                    const struct power_supply_desc *desc,
 851                                    const struct power_supply_config *cfg,
 852                                    bool ws)
 853 {
 854         struct device *dev;
 855         struct power_supply *psy;
 856         int rc;
 857
 858         if (!parent)
 859                 pr_warn("%s: Expected proper parent device for '%s'\n",
 860                         __func__, desc->name);
 861
 862         psy = kzalloc(sizeof(*psy), GFP_KERNEL);
 863         if (!psy)
 864                 return ERR_PTR(-ENOMEM);
 865
 866         dev = &psy->dev;
 867
 868         device_initialize(dev);
 869
 870         dev->class = power_supply_class;
 871         dev->type = &power_supply_dev_type;
 872         dev->parent = parent;
 873         dev->release = power_supply_dev_release;
 874         dev_set_drvdata(dev, psy);
 875         psy->desc = desc;
 876         if (cfg) {
 877                 psy->drv_data = cfg->drv_data;
 878                 psy->of_node = cfg->of_node;
 879                 psy->supplied_to = cfg->supplied_to;
 880                 psy->num_supplicants = cfg->num_supplicants;
 881         }
 882
 883         rc = dev_set_name(dev, "%s", desc->name);
 884         if (rc)
 885                 goto dev_set_name_failed;
 886
 887         INIT_WORK(&psy->changed_work, power_supply_changed_work);
 888         INIT_DELAYED_WORK(&psy->deferred_register_work,
 889                           power_supply_deferred_register_work);
 890
 891         rc = power_supply_check_supplies(psy);
 892         if (rc) {
 893                 dev_info(dev, "Not all required supplies found, defer probe\n");
 894                 goto check_supplies_failed;
 895         }
 896
 897         spin_lock_init(&psy->changed_lock);
 898         rc = device_add(dev);
 899         if (rc)
 900                 goto device_add_failed;
 901
 902         rc = device_init_wakeup(dev, ws);
 903         if (rc)
 904                 goto wakeup_init_failed;
 905
 906         rc = psy_register_thermal(psy);
 907         if (rc)
 908                 goto register_thermal_failed;
 909
 910         rc = psy_register_cooler(psy);
 911         if (rc)
 912                 goto register_cooler_failed;
 913
 914         rc = power_supply_create_triggers(psy);
 915         if (rc)
 916                 goto create_triggers_failed;
 917
 918         /*
 919          * Update use_cnt after any uevents (most notably from device_add()).
 920          * We are here still during driver's probe but
 921          * the power_supply_uevent() calls back driver's get_property
 922          * method so:
 923          * 1. Driver did not assigned the returned struct power_supply,
 924          * 2. Driver could not finish initialization (anything in its probe
 925          *    after calling power_supply_register()).
 926          */
 927         atomic_inc(&psy->use_cnt);
 928         psy->initialized = true;
 929
 930         queue_delayed_work(system_power_efficient_wq,
 931                            &psy->deferred_register_work,
 932                            POWER_SUPPLY_DEFERRED_REGISTER_TIME);
 933
 934         return psy;
 935
 936 create_triggers_failed:
 937         psy_unregister_cooler(psy);
 938 register_cooler_failed:
 939         psy_unregister_thermal(psy);
 940 register_thermal_failed:
 941 wakeup_init_failed:
 942         device_del(dev);
 943 device_add_failed:
 944 check_supplies_failed:
 945 dev_set_name_failed:
 946         put_device(dev);
 947         return ERR_PTR(rc);
 948 }
 949
 950 /**
 951  * power_supply_register() - Register new power supply
 952  * @parent:     Device to be a parent of power supply's device, usually
 953  *              the device which probe function calls this
 954  * @desc:       Description of power supply, must be valid through whole
 955  *              lifetime of this power supply
 956  * @cfg:        Run-time specific configuration accessed during registering,
 957  *              may be NULL
 958  *
 959  * Return: A pointer to newly allocated power_supply on success
 960  * or ERR_PTR otherwise.
 961  * Use power_supply_unregister() on returned power_supply pointer to release
 962  * resources.
 963  */
 964 struct power_supply *__must_check power_supply_register(struct device *parent,
 965                 const struct power_supply_desc *desc,
 966                 const struct power_supply_config *cfg)
 967 {
 968         return __power_supply_register(parent, desc, cfg, true);
 969 }
 970 EXPORT_SYMBOL_GPL(power_supply_register);
 971
 972 /**
 973  * power_supply_register_no_ws() - Register new non-waking-source power supply
 974  * @parent:     Device to be a parent of power supply's device, usually
 975  *              the device which probe function calls this
 976  * @desc:       Description of power supply, must be valid through whole
 977  *              lifetime of this power supply
 978  * @cfg:        Run-time specific configuration accessed during registering,
 979  *              may be NULL
 980  *
 981  * Return: A pointer to newly allocated power_supply on success
 982  * or ERR_PTR otherwise.
 983  * Use power_supply_unregister() on returned power_supply pointer to release
 984  * resources.
 985  */
 986 struct power_supply *__must_check
 987 power_supply_register_no_ws(struct device *parent,
 988                 const struct power_supply_desc *desc,
 989                 const struct power_supply_config *cfg)
 990 {
 991         return __power_supply_register(parent, desc, cfg, false);
 992 }
 993 EXPORT_SYMBOL_GPL(power_supply_register_no_ws);
 994
 995 static void devm_power_supply_release(struct device *dev, void *res)
 996 {
 997         struct power_supply **psy = res;
 998
 999         power_supply_unregister(*psy);
1000 }
1001
1002 /**
1003  * devm_power_supply_register() - Register managed power supply
1004  * @parent:     Device to be a parent of power supply's device, usually
1005  *              the device which probe function calls this
1006  * @desc:       Description of power supply, must be valid through whole
1007  *              lifetime of this power supply
1008  * @cfg:        Run-time specific configuration accessed during registering,
1009  *              may be NULL
1010  *
1011  * Return: A pointer to newly allocated power_supply on success
1012  * or ERR_PTR otherwise.
1013  * The returned power_supply pointer will be automatically unregistered
1014  * on driver detach.
1015  */
1016 struct power_supply *__must_check
1017 devm_power_supply_register(struct device *parent,
1018                 const struct power_supply_desc *desc,
1019                 const struct power_supply_config *cfg)
1020 {
1021         struct power_supply **ptr, *psy;
1022
1023         ptr = devres_alloc(devm_power_supply_release, sizeof(*ptr), GFP_KERNEL);
1024
1025         if (!ptr)
1026                 return ERR_PTR(-ENOMEM);
1027         psy = __power_supply_register(parent, desc, cfg, true);
1028         if (IS_ERR(psy)) {
1029                 devres_free(ptr);
1030         } else {
1031                 *ptr = psy;
1032                 devres_add(parent, ptr);
1033         }
1034         return psy;
1035 }
1036 EXPORT_SYMBOL_GPL(devm_power_supply_register);
1037
1038 /**
1039  * devm_power_supply_register_no_ws() - Register managed non-waking-source power supply
1040  * @parent:     Device to be a parent of power supply's device, usually
1041  *              the device which probe function calls this
1042  * @desc:       Description of power supply, must be valid through whole
1043  *              lifetime of this power supply
1044  * @cfg:        Run-time specific configuration accessed during registering,
1045  *              may be NULL
1046  *
1047  * Return: A pointer to newly allocated power_supply on success
1048  * or ERR_PTR otherwise.
1049  * The returned power_supply pointer will be automatically unregistered
1050  * on driver detach.
1051  */
1052 struct power_supply *__must_check
1053 devm_power_supply_register_no_ws(struct device *parent,
1054                 const struct power_supply_desc *desc,
1055                 const struct power_supply_config *cfg)
1056 {
1057         struct power_supply **ptr, *psy;
1058
1059         ptr = devres_alloc(devm_power_supply_release, sizeof(*ptr), GFP_KERNEL);
1060
1061         if (!ptr)
1062                 return ERR_PTR(-ENOMEM);
1063         psy = __power_supply_register(parent, desc, cfg, false);
1064         if (IS_ERR(psy)) {
1065                 devres_free(ptr);
1066         } else {
1067                 *ptr = psy;
1068                 devres_add(parent, ptr);
1069         }
1070         return psy;
1071 }
1072 EXPORT_SYMBOL_GPL(devm_power_supply_register_no_ws);
1073
1074 /**
1075  * power_supply_unregister() - Remove this power supply from system
1076  * @psy:        Pointer to power supply to unregister
1077  *
1078  * Remove this power supply from the system. The resources of power supply
1079  * will be freed here or on last power_supply_put() call.
1080  */
1081 void power_supply_unregister(struct power_supply *psy)
1082 {
1083         WARN_ON(atomic_dec_return(&psy->use_cnt));
1084         psy->removing = true;
1085         cancel_work_sync(&psy->changed_work);
1086         cancel_delayed_work_sync(&psy->deferred_register_work);
1087         sysfs_remove_link(&psy->dev.kobj, "powers");
1088         power_supply_remove_triggers(psy);
1089         psy_unregister_cooler(psy);
1090         psy_unregister_thermal(psy);
1091         device_init_wakeup(&psy->dev, false);
1092         device_unregister(&psy->dev);
1093 }
1094 EXPORT_SYMBOL_GPL(power_supply_unregister);
1095
1096 void *power_supply_get_drvdata(struct power_supply *psy)
1097 {
1098         return psy->drv_data;
1099 }
1100 EXPORT_SYMBOL_GPL(power_supply_get_drvdata);
1101
1102 static int __init power_supply_class_init(void)
1103 {
1104         power_supply_class = class_create(THIS_MODULE, "power_supply");
1105
1106         if (IS_ERR(power_supply_class))
1107                 return PTR_ERR(power_supply_class);
1108
1109         power_supply_class->dev_uevent = power_supply_uevent;
1110         power_supply_init_attrs(&power_supply_dev_type);
1111
1112         return 0;
1113 }
1114
1115 static void __exit power_supply_class_exit(void)
1116 {
1117         class_destroy(power_supply_class);
1118 }
1119
1120 subsys_initcall(power_supply_class_init);
1121 module_exit(power_supply_class_exit);
1122
1123 MODULE_DESCRIPTION("Universal power supply monitor class");
1124 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
1125               "Szabolcs Gyurko, "
1126               "Anton Vorontsov <cbou@mail.ru>");
1127 MODULE_LICENSE("GPL");